This invention relates generally to food packaging and particularly to techniques for packaging food products in a modified gaseous atmosphere.
It has been proposed to package a variety of food products in modified atmosphere packaging. For example, meat products may have their shelf life extended if they are packaged in a reduced oxygen atmosphere until the time of sale is near. Thereafter, the packages can be exposed to a higher oxygen content environment causing the red meat product to "bloom", changing to the red color more familiar to retail consumers. Exemplary packages that facilitate the modified atmosphere packaging of meat are U.S. Pat. Nos. 5,439,132 and 5,419,096, hereby expressly incorporated by reference herein.
While oxygen exposure is detrimental to the shelf life of certain products, it is essential to the shelf life of other products, such as lettuce, bread and other items. In these cases, it is important to the texture and freshness of the product that it be exposed to a normal atmospheric environment.
Commercial food packages must be amenable to high speed packaging operations. Thus, any practical food package must not only have advantageous functional features, but it must also be designed to facilitate high speed manufacture, essential to achieving low cost. One exemplary high speed food packaging apparatus which is capable of modified atmosphere packaging is disclosed in U.S. Pat. No. 5,479,759, hereby expressly incorporated herein by reference.